And if the proposition be true, a standard measure of value is of so much importance in political economy, and the one proposed is at all times so very ready and easy of application,[L] that there is scarcely any part of the science in which it will not tend to simplify and facilitate our inquiries. To advert shortly to a few points on which there have been some differences of opinion. On the subject of rents, such a standard would determine, among other things, that, as the increase in the _value_ of corn is only measured by a decrease in the corn wages of labour, such increase of value is a very inconsiderable source of the increase of rents compared with improvements in agriculture; and on the same principle that, if tithes do not fall mainly on the labourer, the acknowledged diminution in the _corn_ rents of the landlord, occasioned by tithes, cannot be balanced by an increase of their value, and that, consequently, tithes must fall mainly on the landlord. On the subject of labour it would determine, that the increasing _value_ of the funds destined for the maintenance of labour can alone occasion an increase in the demand for it, or the will and power to employ a greater number of labourers; and that it is consistent with theory, as well as general experience, that high corn wages, in proportion to the quantity of work done, should frequently occur with a very slack demand for labour;[M] or, in other words, that when the _value_ of the whole produce falls from excess of supply compared with the demand, it cannot have the power of setting the same number of labourers to work. On the subject of profits, it would show, that they are determined, not by the varying value of a given quantity of labour compared with the constant value of the commodities which it produces, but, as is more conformable to our experience, by the variable value of the commodities produced by a given quantity of labour, compared with the constant value of such labour; and that profits never, on any occasion, rise or fall, unless the value of the produce of a given quantity of labour rises or falls, either from the temporary or ordinary state of the demand and supply. On the subject of the distinction between wealth and value, it would show, that though they are by no means the same, they are much more closely connected than they have of late been supposed to be; and that the best practical measure of the relative wealth of different countries would be the quantity of common labour which the value of the whole annual produce of each country would enable it to command at the actual price of the time, which in some rich countries might amount to above double the number of families actually employed, and in poor countries might not greatly exceed such number.